They have reason to worry. Last week, an increasingly open climate of racism and xenophobia in Hungary took another turn for the worse when Marton Gyongyosi, a member of the Roma-baiting Jobbik radical nationalist party, declared in Parliament that Jews in government and the legislature were a "national security risk" and demanded that their names be compiled in a registry. Later, in what he described as an apology to his "Jewish compatriots," Gyongyosi said he had been misquoted: He had only meant to warn of the danger posed by Hungarian Jews who serve "Zionist Israel."

No one was fooled by this depressingly familiar strategy, adopted by many European far-right movements -- and groups on the left, too: clumsily camouflaging the vilification of Jews as legitimate criticism of Israel's policies or supposed concern for the Palestinians. The U.S. Embassy condemned Gyongyosi's "outrageous anti-Semitic remarks," representatives of the Hungarian Jewish community said they would consider bringing charges of incitement against the lawmaker, and both the ruling Fidesz Party's parliamentary leader and opposition politicians spoke out at the rally Sunday.

Disturbingly, Prime Minister Viktor Orban took almost a week to add his voice to the reprobation with a vow to protect his country's 100,000 Jews, though he didn't denounce Jobbik by name. Unfortunately, the delay wasn't much of a surprise: In solidifying his hold on power, Orban has shown a disquieting tolerance for Jobbik, the third-biggest party in Parliament, and for its bald appeals to the politics of resentment.

The far-right party has encountered little resistance from the government to its creeping animosity toward the Roma minority and its escalating efforts to rehabilitate unsavory figures such as Admiral Miklos Horthy, the country's pro-Nazi leader during World War II, whose regime colluded with the deportation -- and subsequent murder -- of at least 430,000 Hungarian Jews in 1944.

Earlier this year, the Nobel laureate Elie Wiesel returned Hungary's highest award, the Grand Cross Order of Merit, to protest the participation by government and Fidesz officials in a ceremony honoring the founder of the pro-Nazi and viciously anti-Semitic Arrow Cross militia.

For too long, the European Union has tended to trivialize groups such as Jobbik or the neo-Nazi Golden Dawn in Greece as unfortunate symptoms of the growing pains that accompany the transition from communist tyranny, or as extreme popular reactions to tough economic times that will disappear with renewed prosperity or greater integration in the EU.

This wishful thinking reflects an increasingly obvious institutional flaw in the EU, which has few tools to force its member states to defend the democratic values the union claims to embody. This weakness was most prominent in 2000, when the far-right Freedom Party became a partner in the Austrian government. The EU discovered that while it could exert pressure on countries that were applying to join, it had very little influence with countries that were already members.

Orban has brushed aside European criticism of his appeals to nationalism and his shaky embrace of democracy, including a new constitution that infringes on freedom of the press, the central bank and the independence of the judiciary.

We can hope that Hungary's 2014 elections will make Jobbik an embarrassing historical footnote and sanction Orban's authoritarian bent. In the meantime, however, a failure to harshly condemn these extremist movements -- along with governments such as Orban's that seem content to tolerate them -- will validate and embolden the bullies.

(Max Berley is a member of the Bloomberg View editorial board. E-mail him and follow him on Twitter.)